pgsql: Fix overly large values/nulls arrays

Fix overly large values/nulls arrays

These arrays were sized with Natts_pg_trigger (19) when they should have
been sized with Natts_pg_event_trigger (7). We'd better fix this as
it's clearly a mistake and it could become problematic if
pg_event_trigger were to gain a dozen or so more columns in the future.

No backpatch as there's no actual bug and the column count on those
tables isn't going to change in released versions.

Author: Xin Zhang <zhanghien(at)qq(dot)com>
Discussion: https://postgr.es/m/tencent_05AD0FB321A414EC3661204D2102AA6EF605@qq.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/eb53ff5517e50018539747d75a02d493abc2d232

Modified Files
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src/backend/commands/event_trigger.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)